Relating CP and SP as percentages If the cost price of an article is 40% of its selling price, what percent is the selling price of the cost price?

Introduction / Context:
We are given CP as a fraction of SP and asked to invert the relationship to express SP as a percent of CP. This is a straightforward ratio inversion.

Given Data / Assumptions:

• CP = 40% of SP = 0.40 SP.

Concept / Approach:
From CP = 0.40 SP ⇒ SP/CP = 1/0.40 = 2.5. Convert to percentage by multiplying by 100.

Step-by-Step Solution:
SP/CP = 2.5 ⇒ SP is 2.5 × CP.As a percent, 2.5 × 100 = 250%.

Verification / Alternative check:
Let SP = 100. Then CP = 40. SP as percent of CP = 100 / 40 × 100 = 250% (matches).

Why Other Options Are Wrong:
240% is close but incorrect; 40%, 60%, 200% arise from misreading the base.

Common Pitfalls:
Using CP as 40% of SP but then forgetting to invert correctly when expressing SP relative to CP.

Final Answer:
250